Raw model output on the native 0.25° grid — no MOS, no bias correction, no post-processing. Scores understate operational forecast quality. Read the fairness statement →

CastCheck methodology v0.2 · data through 2026-08-30

New Orleans Intl · NCEP GFS · lead day 1

KMSY · gfs · lead 1

Target day = initialization date + 1 day. This page is a permanent link: the numbers change as history accumulates, the address and the methodology version do not.

Scores use the latest model version segment, gfs-0p25, starting 2026-08-01 — days before that ran a different version of the model and are excluded rather than silently pooled. Of the scored days, 1 carry a QC flag on the observation.

JSON for this page CSV of the daily errors Cite this page

Every number for this combination

All four windows × both initializations × both interpolations × both variables. Errors are computed in °C and shown in °F; CI is a 95 % moving-block bootstrap interval. MAE debiased and skill, debiased remove the constant offset of the window first, so a station that the model always reads a degree too warm is not scored as if it had no skill — compare the two skill columns to see how much of the error is a fixed offset. n QC next to n counts days whose observation carries a QC flag.

VariableInitMethod Windown MAE °F MAE debiased Bias °F RMSE °F ±1 °F±2 °F±3 °F Skill Skill, debiased Period
tmax00Zbilinear30d29 1 QC4.69 [3.89, 5.84]1.94-4.41 [-5.55, -3.58]5.16 [4.12, 6.46]0% [0%, 0%]3%21%-1.06+0.162026-08-02 → 2026-08-30
tmax00Zbilinear90d29 1 QC4.69 [3.79, 6.18]1.94-4.41 [-5.95, -3.12]5.16 [4.01, 6.77]0% [0%, 0%]3%21%-1.06+0.162026-08-02 → 2026-08-30
tmax00Zbilinear365d29 1 QC4.69 [3.80, 6.43]1.94-4.41 [-6.26, -3.11]5.16 [4.02, 7.00]0% [0%, 0%]3%21%-1.06+0.162026-08-02 → 2026-08-30
tmax00Zbilinearall29 1 QC4.69 [3.81, 6.08]1.94-4.41 [-5.97, -3.05]5.16 [4.03, 6.66]0% [0%, 0%]3%21%-1.06+0.162026-08-02 → 2026-08-30
tmax00Znearest30d29 1 QC4.79 [4.03, 5.88]1.91-4.51 [-5.61, -3.71]5.23 [4.26, 6.48]0% [0%, 0%]3%17%-1.11+0.172026-08-02 → 2026-08-30
tmax00Znearest90d29 1 QC4.79 [3.94, 6.22]1.91-4.51 [-5.97, -3.21]5.23 [4.13, 6.79]0% [0%, 0%]3%17%-1.11+0.172026-08-02 → 2026-08-30
tmax00Znearest365d29 1 QC4.79 [3.95, 6.44]1.91-4.51 [-6.28, -3.21]5.23 [4.15, 6.99]0% [0%, 0%]3%17%-1.11+0.172026-08-02 → 2026-08-30
tmax00Znearestall29 1 QC4.79 [3.95, 6.14]1.91-4.51 [-6.01, -3.17]5.23 [4.16, 6.71]0% [0%, 0%]3%17%-1.11+0.172026-08-02 → 2026-08-30
tmax12Zbilinear30d29 1 QC4.84 [3.94, 6.01]1.96-4.57 [-5.75, -3.65]5.26 [4.34, 6.34]3% [0%, 10%]7%17%-1.13+0.152026-08-02 → 2026-08-30
tmax12Zbilinear90d29 1 QC4.84 [3.87, 6.26]1.96-4.57 [-6.15, -3.21]5.26 [4.23, 6.53]3% [0%, 10%]7%17%-1.13+0.152026-08-02 → 2026-08-30
tmax12Zbilinear365d29 1 QC4.84 [3.85, 6.60]1.96-4.57 [-6.58, -3.17]5.26 [4.23, 6.80]3% [0%, 11%]7%17%-1.13+0.152026-08-02 → 2026-08-30
tmax12Zbilinearall29 1 QC4.84 [3.89, 6.24]1.96-4.57 [-6.09, -3.10]5.26 [4.25, 6.54]3% [0%, 10%]7%17%-1.13+0.152026-08-02 → 2026-08-30
tmax12Znearest30d29 1 QC4.96 [4.09, 6.06]1.95-4.69 [-5.81, -3.79]5.35 [4.50, 6.37]3% [0%, 10%]7%10%-1.18+0.162026-08-02 → 2026-08-30
tmax12Znearest90d29 1 QC4.96 [4.04, 6.30]1.95-4.69 [-6.17, -3.35]5.35 [4.39, 6.54]3% [0%, 10%]7%10%-1.18+0.162026-08-02 → 2026-08-30
tmax12Znearest365d29 1 QC4.96 [4.00, 6.61]1.95-4.69 [-6.59, -3.32]5.35 [4.39, 6.82]3% [0%, 11%]7%10%-1.18+0.162026-08-02 → 2026-08-30
tmax12Znearestall29 1 QC4.96 [4.04, 6.29]1.95-4.69 [-6.14, -3.25]5.35 [4.39, 6.55]3% [0%, 10%]7%10%-1.18+0.162026-08-02 → 2026-08-30
tmin00Zbilinear30d29 1 QC1.80 [1.29, 2.28]1.51+1.40 [0.93, 1.85]2.26 [1.73, 2.78]38% [25%, 57%]55%83%-0.09+0.112026-08-02 → 2026-08-30
tmin00Zbilinear90d29 1 QC1.80 [1.34, 2.40]1.51+1.40 [0.88, 1.86]2.26 [1.75, 2.86]38% [23%, 53%]55%83%-0.09+0.112026-08-02 → 2026-08-30
tmin00Zbilinear365d29 1 QC1.80 [1.30, 2.41]1.51+1.40 [0.82, 1.89]2.26 [1.69, 2.91]38% [22%, 55%]55%83%-0.09+0.112026-08-02 → 2026-08-30
tmin00Zbilinearall29 1 QC1.80 [1.32, 2.42]1.51+1.40 [0.84, 1.88]2.26 [1.74, 2.89]38% [23%, 54%]55%83%-0.09+0.112026-08-02 → 2026-08-30
tmin00Znearest30d29 1 QC1.84 [1.33, 2.32]1.52+1.45 [0.99, 1.91]2.30 [1.76, 2.81]38% [25%, 57%]59%76%-0.11+0.102026-08-02 → 2026-08-30
tmin00Znearest90d29 1 QC1.84 [1.37, 2.43]1.52+1.45 [0.93, 1.93]2.30 [1.78, 2.90]38% [23%, 53%]59%76%-0.11+0.102026-08-02 → 2026-08-30
tmin00Znearest365d29 1 QC1.84 [1.33, 2.44]1.52+1.45 [0.88, 1.95]2.30 [1.72, 2.94]38% [22%, 55%]59%76%-0.11+0.102026-08-02 → 2026-08-30
tmin00Znearestall29 1 QC1.84 [1.35, 2.44]1.52+1.45 [0.90, 1.94]2.30 [1.77, 2.94]38% [23%, 54%]59%76%-0.11+0.102026-08-02 → 2026-08-30
tmin12Zbilinear30d29 1 QC1.47 [1.11, 1.83]1.15+1.01 [0.53, 1.42]1.75 [1.44, 2.04]31% [15%, 50%]62%100%+0.11+0.322026-08-02 → 2026-08-30
tmin12Zbilinear90d29 1 QC1.47 [1.16, 1.90]1.15+1.01 [0.46, 1.39]1.75 [1.50, 2.10]31% [12%, 49%]62%100%+0.11+0.322026-08-02 → 2026-08-30
tmin12Zbilinear365d29 1 QC1.47 [1.11, 1.88]1.15+1.01 [0.43, 1.43]1.75 [1.45, 2.07]31% [12%, 50%]62%100%+0.11+0.322026-08-02 → 2026-08-30
tmin12Zbilinearall29 1 QC1.47 [1.14, 1.92]1.15+1.01 [0.39, 1.46]1.75 [1.47, 2.14]31% [12%, 50%]62%100%+0.11+0.322026-08-02 → 2026-08-30
tmin12Znearest30d29 1 QC1.49 [1.12, 1.85]1.15+1.05 [0.57, 1.47]1.77 [1.46, 2.07]31% [15%, 50%]62%100%+0.10+0.322026-08-02 → 2026-08-30
tmin12Znearest90d29 1 QC1.49 [1.17, 1.93]1.15+1.05 [0.52, 1.44]1.77 [1.52, 2.12]31% [12%, 49%]62%100%+0.10+0.322026-08-02 → 2026-08-30
tmin12Znearest365d29 1 QC1.49 [1.12, 1.89]1.15+1.05 [0.48, 1.47]1.77 [1.46, 2.08]31% [12%, 50%]62%100%+0.10+0.322026-08-02 → 2026-08-30
tmin12Znearestall29 1 QC1.49 [1.15, 1.96]1.15+1.05 [0.45, 1.51]1.77 [1.49, 2.16]31% [12%, 50%]62%100%+0.10+0.322026-08-02 → 2026-08-30

+ model too warm · − model too cold · bias interval includes zero · ★ lowest MAE · = not distinguishable from the leader · ▼ significantly worse · n < 30 greyed and unranked · CI is a 95 % moving-block bootstrap interval.

Daily error, last 90 days

Daily forecast minus observed error in °F for NCEP GFS at KMSY, lead day 1, 00Z bilinear tmax+20+100-10-202026-08-02: +4.07 °F2026-08-03: -2.33 °F2026-08-04: -5.8 °F2026-08-05: -5.84 °F2026-08-06: -4.49 °F2026-08-07: -3.31 °F2026-08-08: -3.65 °F2026-08-09: -2.32 °F2026-08-10: -3.31 °F2026-08-11: -6.27 °F2026-08-12: -1.75 °F2026-08-13: -2.72 °F2026-08-14: -5.75 °F2026-08-15: -6.9 °F2026-08-16: -4.43 °F2026-08-17: -3.25 °F2026-08-18: -3.58 °F2026-08-19: -2.95 °F2026-08-20: -3.97 °F2026-08-21: -3.17 °F2026-08-22: -5.36 °F2026-08-23: -3.74 °F2026-08-24: -2.04 °F2026-08-25: -6.4 °F2026-08-26: -7.14 °F2026-08-27: -6.56 °F2026-08-28: -12.38 °F2026-08-29: -6.92 °F2026-08-30: -5.48 °F2026-08-022026-08-30°F, forecast − observed
Forecast − observed, °F, 00Z bilinear daily maximum. The dashed line is zero; the thick line is a centred 7-day mean, drawn only where the whole window is present. Gaps are days with no score, never interpolation. Hover a point for its date and value.
The same series as a table (29 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-5.48
2026-08-29-6.92
2026-08-28-12.38
2026-08-27-6.56
2026-08-26-7.14
2026-08-25-6.40
2026-08-24-2.04
2026-08-23-3.74
2026-08-22-5.36
2026-08-21-3.17
2026-08-20-3.97
2026-08-19-2.95
2026-08-18-3.58
2026-08-17-3.25
2026-08-16-4.43
2026-08-15-6.90
2026-08-14-5.75
2026-08-13-2.72
2026-08-12-1.75
2026-08-11-6.27
2026-08-10-3.31
2026-08-09-2.32
2026-08-08-3.65
2026-08-07-3.31
2026-08-06-4.49
2026-08-05-5.84
2026-08-04-5.80
2026-08-03-2.33
2026-08-02+4.07

Error distribution

Distribution of the signed daily error in °F for NCEP GFS at KMSY, lead day 1-20 to -18 °F: 0 days-18 to -16 °F: 0 days-16 to -14 °F: 0 days-14 to -12 °F: 1 day-12 to -10 °F: 0 days-10 to -8 °F: 0 days-8 to -6 °F: 6 days-6 to -4 °F: 7 days-4 to -2 °F: 13 days-2 to 0 °F: 1 day0 to 2 °F: 0 days2 to 4 °F: 0 days4 to 6 °F: 1 day6 to 8 °F: 0 days8 to 10 °F: 0 days10 to 12 °F: 0 days12 to 14 °F: 0 days14 to 16 °F: 0 days16 to 18 °F: 0 days18 to 20 °F: 0 daysdashed: P50 |e| 4.07 · P90 |e| 6.9 °F-200+20 °Fn = 29 days
All scored days for 00Z bilinear daily maximum, 20 equal bins. The dashed marks are the 50th and 90th percentiles of the absolute error, mirrored on both sides. Hover a bar for its bin and count.
Bin counts as a table
From °FTo °FDays
-20.00-18.000
-18.00-16.000
-16.00-14.000
-14.00-12.001
-12.00-10.000
-10.00-8.000
-8.00-6.006
-6.00-4.007
-4.00-2.0013
-2.00+0.001
+0.00+2.000
+2.00+4.000
+4.00+6.001
+6.00+8.000
+8.00+10.000
+10.00+12.000
+12.00+14.000
+14.00+16.000
+16.00+18.000
+18.00+20.000

Month by month

00Z bilinear daily maximum, newest first.

Monthn MAE °FBias °F
2026-08294.69 -4.41

Availability

ModelScored period DaysCoverage
NCEP GFS2026-08-02 → 2026-08-30 29
NCEP GFS2026-08-02 → 2026-08-30 29
NCEP GFS2026-08-02 → 2026-08-30 29
NCEP GFS2026-08-02 → 2026-08-30 29

Compared with other models

Paired bootstrap on the days both models cover (90d, 00Z, bilinear, daily maximum). Negative means NCEP GFS has the lower MAE. "Distinguishable" means the 95 % interval excludes zero.

Other modelCommon days MAE difference °FDistinguishable
ECMWF AIFS Single 29 +0.38 [-0.45, 1.56] no
Aurora (GFS init) 1 -1.73 [-1.73, -1.73] yes
Aurora (IFS init) 2 -0.70 [-1.65, 0.26] no
FourCastNet v2 (GFS init) 1 +2.60 [2.60, 2.60] yes
FourCastNet v2 (IFS init) 2 +3.02 [2.83, 3.22] yes
GraphCast (GFS init) 1 +0.17 [0.17, 0.17] yes
GraphCast (IFS init) 27 -0.74 [-1.43, 0.20] no
ECMWF IFS HRES 23 +0.76 [-0.57, 1.56] no
Pangu-Weather (GFS init) 1 +0.04 [0.04, 0.04] yes
Pangu-Weather (IFS init) 2 +1.96 [0.21, 3.71] yes
Persistence (baseline) 29 +2.41 [0.41, 3.46] yes

Cite this page

ShortCastCheck, KMSY gfs lead 1, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KMSY/model/gfs/lead/1/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KMSY (New Orleans Intl), model gfs, lead day 1. Methodology version 0.2, schema version 0.1, data through 2026-08-30. Accessed 2026-08-31. https://castcheck.zifanzhang.com/station/KMSY/model/gfs/lead/1/

Accessed2026-08-31 (data through 2026-08-30; page built 2026-08-31T03:52:06+00:00)

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